“While scientists have made significant strides in understanding the mechanics of sleep, including deep sleep, some aspects of how and why deep sleep happens remain a mystery. Deep sleep, also known as slow-wave sleep, is crucial for bodily restoration and recovery, but the precise mechanisms regulating its onset and maintenance are not fully elucidated. “
Srila Jiva Goswami has likened deep sleep to the Brahman, the spiritual effulgence of Divinity where many consciousness particles take shelter .
How some of these consciousness particles arrive at , and are in the glance of Mahavisnu , who are consequently impregnated into matter, is contemplated upon differently by different Vedic schools of thought.
But Srila BR Sridha Swami tells , just as it is not clear how a deep sleep condition is suddenly brought back to space time existence, ie , we suddenly awaken , its somewhat beyond the comprehension of how the jiva finds himself in the material world and within the glance of Visnu….the Tatasta sakti is key to understanding and a free will that is facilitated , by the supreme facilitator,  thus Maha Visnu appears to take a functional role , indeed Srila Jiva Goswami in his Bhagavat Sandarbha says it is the individual living beings who want the material world not Him .

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